Nonlinear analysis of laterally loaded rock-socketed shafts

In this paper, a nonlinear continuum method is developed to predict the loa d-displacement response of drilled shafts under lateral loading. The method can consider drilled shafts in a continuum consisting of a soil layer over lying a rock mass layer. The deformation modulus of the soil is assumed to vary linearly with depth, and the deformation modulus of the rock mass is a ssumed to vary linearly with depth and then to stay constant below the shaf t tip. The effect of soil and/or rock mass yielding on the behavior of shaf ts is considered by assuming that the soil and/or rock mass behaves linearl y elastically at small strain levels and yields when the soil and/or rock m ass reaction force p (force/length) exceeds the ultimate resistance p(ult) (force/length). For the calculation of the ultimate resistance p(ult) of th e soil, methods that are available in the literature are used. To calculate the ultimate resistance p(ult) of the rock mass, a method based on the Hoe k-Brown strength criterion is proposed. The proposed method is verified by comparing its results with available elastic solutions and field test data, and it is finally applied in the design of a bridge foundation in Massachu setts.